Tenn. Code Ann. § 10-7-102

The county legislative body, on demand of the register, shall procure for the register's office well-bound books for the purpose of registering therein such instruments of writing as are required by law to be registered, the cost of which shall be paid by the trustee of the county, on the warrant of the county mayor, which shall be issued on the register producing before the county mayor the receipt of the person from whom the books were purchased, and making affidavit that the register has paid, or is bound to pay, the sum specified in the receipt.